Grid moving apparatus for minimizing image information of an object

ABSTRACT

An improved grid moving method of an object image and an apparatus using the same which are capable of reducing the amount of information with respect to the image of an object by moving the grid in accordance with a position in which an image of the object having shape information exists, which include the steps of: a moving step for forming a grid over an image of an object having shape information, segmenting the image into a plurality of unit regions, and moving the formed grid; a judging step for judging an amount of the information at each position to which the grid is moved in the moving step; a detecting step for detecting a position at which the amount of the information is reduced; a compaction step for reforming the grid in accordance with the position detected in the detecting step and for coding the image of the object existing in unit regions of the reformed grid; and a motion estimation step for reforming the grid in accordance with the position detected in the detecting step and for estimating the motion of the image of the object in the unit regions in which the image of the object exists among the unit regions segmented by the reformed grid.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a grid moving method for minimizingimage information of an object image and an apparatus therefore and acompaction/motion estimation method using the grid moving method and anapparatus therefor, and particularly to an improved grid moving methodfor an object image and an apparatus therefor and a compaction/motionestimation method using the grid moving method and an apparatus thereforwhich are capable of forming a grid with respect to an image of apredetermined object having shape information and, in a region of animage, dividing the region of the image into a plurality of unitregions, moving the formed grid and detecting a position at which theamount of information is reduced when performing a compaction orestimating a motion of an object. In addition, the present invention isbasically directed to reforming the grid to a position at which theamount of information is reduced by moving the grid, and is directed toseparating and coding each unit region in which an image of the objectexist from the reformed grid and using the grid movement of the image ofan object of which the motion is estimated.

2. Description of the Related Art

Conventionally, since an image of an object having a predetermined shapecontains a great amount of image data, when storing the image data in arecording/writing medium, a large space is necessary for storing thedata. In addition, transmitting the data takes too much time, so it isdifficult to transmit the data in real time.

Therefore, the image of the object is coded, and the motion of the imageis estimated and then the amount of the information in the image isreduced for storing the information in a predetermined recording/writingmedium. Thereafter, the information is transmitted to a predetermineddestination in real time.

When coding an image of an object, a vector quantumization method or adiscrete cosine transform (DCT) method is used.

Recently, a shape adaptive discrete cosine transform (SADCT) method hasbeen effectively used in industry. This method is very effective forobject-based compaction.

The above-mentioned shape adaptive discrete cosine transform method isdirected to forming a grid with respect to an image frame, dividing animage of an object into a plurality of unit regions each havingpredetermined size and shape information, separating a unit region fromthe plurality of the unit regions in which an image of the object existsand then coding the unit region.

In addition, when the unit region contains an image to be coded, theeffectiveness between a two-dimensional region DCT and a compactionbecome identical in the shape adaptive discrete cosine transform. Whenthe unit region does not contain the image to be coded, the pixel, inwhich an image of an object exists, is processed with respect to theX-axis in a one-dimensional discrete cosine transform method, and aresult of the above X-axis-based process is processed with respect tothe Y-axis in a one-dimensional discrete cosine transform method.Thereafter, the final result value is obtained.

The shape adaptive discrete cosine transform method is further directedto reducing the number of unit regions in which an image of an objectexists and performing the compaction after substantially filling theimage of the object in the unit region, thus enhancing the compaction ofa transform constant.

Therefore, when performing the shape adaptive discrete cosine transformprocess, the image of the object to be coded should preferably besubstantially filled in each unit region, and then the number of unitregions in which an image of the object exists is effectively reduced.

The above-described shape adaptive discrete cosine transform processwill now be described in more detail with reference to FIGS. 1A through3F.

FIGS. 1A and 1B show grid patterns formed in one frame.

As shown therein, one frame is divided into a plurality of rows andcolumns which are consisted of a plurality of unit regions 21 having thesame size and shape in cooperation with a P×Q number of X-axis grid andY-axis grid 11 and 13 spaced apart from one another at a regulardistance.

A unit region 21 may be formed in various shapes.

For example, the unit region 21 is formed in a regular square or arectangular form by the X-axis and Y-axis grid 11 and 13. In addition,as shown in FIG. 2A. A unit region 21 may be formed as a horizontallylying triangle or a horizontally upside down triangle, and neighboringtriangles form rectangular shapes bounded by the slant grids 15 and 17.As shown in FIG. 2B, a unit region 21 is formed by vertically lyingtriangles and neighboring triangles form rectangular shapes bounded bythe slant grids 15 and 17.

In addition, as shown in FIG. 2C, the unit region 21 is formed as a 45°rotated square by the slant grids 15 and 17, and as shown in FIGS. 2Dand 2E, the unit region 21 is formed in a hexagonal shape by the slantgrids 15 and 17. As shown in FIG. 2F, the unit region 21 is formed in anoctagonal form having a 45° rotated small square between the neighboringoctagons. In this example, two different shaped unit regions 21 areconcurrently used.

Any shape which spatially and evenly divides the image frame may be usedfor the unit region 21.

A square- or rectangular-shaped unit region 21 which is defined by anX-axis grid 11 and Y-axis grid 13 will now be explained.

As shown in FIG. 1B, the unit region 21 is formed of an M×N number ofunit pixels 23 in the X-axis and Y-axis directions. For example, oneunit region 21 is formed of an 8×8 number of unit pixels 23 or is formedof a 16×16 number of unit pixels 23.

In addition, a unit region 21 is defined as an M×N number of blocks inaccordance with the number of unit pixels 23. As shown in FIG. 1B, theunit region 21 refers to an 8×8 number of blocks corresponding to unitpixels.

FIG. 3A shows an image (shown as the hatched portion) havingpredetermined shape information in a unit region 21 formed of an 8×8number of unit pixels 23.

For the shape adaptive discrete cosine transform with respect to theimage of an object, as shown in FIG. 3B, the image of the object isfilled from the upper side margin portion of the unit region 21, andthen the one-dimensional cosine transform is performed with respect tothe Y-axis which is shown in the vertical direction.

The one-dimensional discrete cosine transform is performed as shown inFIG. 3D.

When the one-dimensional discrete cosine transform is completed withrespect to the Y-axis, the image of the object is filled from the leftside margin portion of the unit region 21, as shown in FIG. 3E, and thenthe one-dimensional discrete cosine transform is performed with respectto the X-axis which is shown in the horizontal direction.

When the one-dimensional discrete cosine transform is completed withrespect to the X-axis, as shown in FIG. 3F, the shape adaptive discretecosine transform with respect to the Y-axis and X-axis is completed.

Thereafter, a zig-zag scan is performed with respect to the final shape,as shown in FIG. 3F, which is obtained by the above-mentioned shapeadaptive discrete cosine transform. For example, the zig-zag scan isperformed diagonally from the leftmost side and the uppermost side tothe rightmost side and the lowermost side.

However, the conventional shape adaptive discrete cosine transform isdirected to performing the shape adaptive discrete cosine transform inaccordance with the position in which the image of an object existswithout moving the position of the grid.

Therefore, the bit rate per frame is high, and since the number of theunit regions in which the image of the object exists in numerous, thereis a restriction on the ability to reduce an amount of compactioninformation which is obtained by coding the image of the object and theamount of motion information which is obtained by estimating the motionof the object.

In addition, when coding an object in the conventional discrete cosinetransform method or the vector quantumization, since the compaction isperformed without moving the position of the grid in accordance with theposition in which the image of the object exists, the hit rate per frameis high as in the shape adaptive discrete cosine transform, and sincethe number of unit regions in which the image of the object exists innumerous, there is a restriction on the ability to reduce the amount ofcompaction information and the amount of motion information.

Meanwhile, when coding the image of a moving object among the images ofan object having predetermined shape information, an object-based movingimage coding method is generally used in the industry.

The above-mentioned object-based moving image coding method is directedto segmenting the image of the object in a background in which there isnot a moving image and a changed region which is defined by the movingimage of the object.

In addition, the moving object of the changed region is segmented into amotion compensable object and a motion compensable failed object throughmotion estimation.

Here, the motion compensable object refers to the moving object having apredetermined theory such as a horizontal movement, a rotationalmovement, a lineal movement, and the like in a state that the object ina three-dimensional space is converted into a two-dimensional image ofthe object. In addition, the motion compensable failed object refers toan object which is not adaptable with respect to the above-mentionedtheroy.

When transmitting and storing the image of the object the motioncompensable object process is directed to detecting motion informationof the image of the object.

In addition, the image of the motion compensable failed object and theimage of the exposed object are most effectively coded so as to reducethe amount of information, which is then transmitted and stored.

Since the amount of information with respect to the image of the motioncompensable failed object is about 60-70% of the total amount of theinformation to be transmitted, many studies have been conducted, in theindustry, so as to reduce the amount of information transmitted.

The motion estimation of the motion compensable object is directed tosegmenting and estimating the moving portion of the moving image from apicture of the previous frame so as to minimize the amount of motioninformation.

However, since the variables with respect to the moving object arevarious, it is difficult to effectively extract, transmit, and storemotion information in response to the immediate movement of the object.

Therefore, in the industry, it is urgently needed to transmit and storepicture information of a high resolution having a small amount ofinformation with respect to the motion compensable object in the motionestimation method.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide a gridmoving method for minimizing image information of an object image and anapparatus using the grid moving method and a compaction/motionestimation method using the grid moving method and an apparatus thereforwhich overcome the problems encountered in the conventional method of anobject image and an apparatus therefor and a conventionalcompaction/motion estimation method and an apparatus therefor.

It is another object of the present invention to provide a grid movingmethod for an object image and an apparatus using the grid moving methodwhich are capable of reducing amount of information with respect to theimage of an object by moving the grid in accordance with a position inwhich an image of the object having predetermined shape informationexists.

It is another object of the present invention to provide a grid movingmethod for an object image and an apparatus using the grid moving methodwhich are capable of reducing the number of unit regions in which animage of the object exists by moving the grid so as to reduce the amountof the information with respect to the image of the object.

It is another object of the present invention to provide an image signalcoding apparatus and a compaction method using a grid moving methodwhich are capable of reducing the amount of compaction information bycompacting the unit regions in which the image of the object existsamong the unit regions segmented by the grid moved in accordance withthe position in which the image of the object exists.

It is another object of the present invention to provide an image signalcoding apparatus and a compaction method using a grid moving methodwhich are capable of reducing the amount of information by compactingthe unit region in which the image of a motion compensable failed objecthaving predetermined shape information exists among the unit regionswhich is segmented by the grid moved in accordance with the position inwhich the image of the motion compensable failed object exists.

It is another object of the present invention to provide a motionestimation apparatus and a method of the motion estimation apparatususing a grid moving method which is capable of estimating the motioninformation as a unit region in which an image of the motion compensableobject exists among the unit region which is segmented by the grid whichis moved in accordance with the position in which an image of the motioncompensable object exists.

The achieve the above objects, the present invention is basicallydirected to segmenting an image of an object having predetermined shapeinformation with a grid, detecting a position in which the amount ofthis information can be reduced by moving the position of the grid alongthe X-axis or Y-axis directions, and moving the grid to the position inwhich the amount of information can be reduced.

To achieve the above objects, the present invention is directed tomoving the position of the grid so that the image of the object can bepositioned in the minimum number of unit regions so as to reduce theamount of information with respect to the image of the object.

To achieve the above objects, the present invention is directed todetecting the number of unit regions in which the image of an objectexists and moving the position of the grid so that the image of theobject exists in the minimum number of unit regions and coding the imageof the object existing in the detected unit regions so as to minimizethe amount of information.

To achieve the above objects, the present invention is directed tojudging the unit regions in which the image of the object exists in astate that the position of the grid is moved so that the image of theobject can exists in the minimum number of unit regions, and estimatingthe motion of the object using the judged unit region and detecting theposition of the grid using the information of the object.

To achieve the objects above, there is provided a grid moving method ofan object image, including the steps of: a segmenting step for forming agrid over an image of an object having predetermined shape informationand for segmenting the image into a plurality of unit regions; and adetecting step for detecting a position at which the amount ofinformation is reduced by moving the grid formed in the segmenting step.

To achieve the objects above, there is provided a compaction/motionestimation method, including the steps of: a moving step for forming agrid over an image of an object having predetermined shape information,segmenting the image into a plurality of unit regions, and moving theformed grid; a judging step for judging the amount of information ateach position to which the grid is moved in the moving step; a detectingstep for detecting a position at which the amount of information isreduced; a compaction step for reforming the grid in accordance with theposition detected in the detecting step and for coding the image of theobject existing in each unit region of the reformed grid; and a motionestimation step for reforming the grid in accordance with the positiondetected in the detecting step and for estimating the motion of theimage of the object in the unit regions in which the image of the objectexists among the unit regions segmented by the reformed grid.

To achieve the objects above, there is provided a compaction method,including the steps of: a moving step for forming a grid over an imageof an object having predetermined shape information, segmenting theimage into a plurality of unit regions, and for moving the formed grid;a judging step for judging the amount of information at each position towhich the grid is moved in the moving step; a detecting step fordetecting a position at which the amount of information is reduced inthe judging step; and a compaction step for reforming the grid inaccordance with the position detected in the detecting step and codingthe image of the object existing in the unit region of the reformedgrid.

To achieve the objects above, there is provided a motion estimationmethod, including the steps of: a moving step for forming a grid over animage of an object having predetermined shape information, segmentingthe image into a plurality of unit regions, and moving the formed grid;a judging step for judging the amount of information at each position towhich the grid is moved in the moving step; a detecting step fordetecting a position at which the amount of information is reduced inthe judging step; and a motion estimation step for reforming the grid inaccordance with the position detected in the detecting step and forestimating the motion of the image of the object in the unit regions inwhich the image of the object exist among the unit regions by thereformed grid.

To achieve the objects above, there is provided a compaction/motionestimation method, including the steps of: a separating step forestimating the motion of an image of an object having predeterminedshape information and for separating a motion compensable failed objectimage and a motion compensable object image; a first moving step forforming a grid over the motion compensable failed object image separatedin the separating step, segmenting the image into a plurality of unitregions, and moving the grid; a first judging step for judging theamount of information at each position to which the grid is moved in thefirst moving step; a first detecting step for detecting a position atwhich the amount of information is reduced in the first judging step; acompaction step for reforming the grid in accordance with the positiondetected in the first detecting step and for coding the unit regions inwhich the image of the motion compensable failed object exists fromamong the unit regions which is segmented by the reformed grid; a secondmoving step for forming a grid over the image of the motion compensableobject separated in the separating step, segmenting the image into aplurality of unit regions, and moving the grid; a second judging stepfor judging an amount of information at each position to which the gridis moved in the second moving step; a second detecting step fordetecting a position at which the amount of information is reduced inthe second judging step; and a motion estimating step for reforming thegrid in accordance with the position detected in the second detectingstep and for estimating the motion of the image of the motioncompensable object using the unit regions in which the image of themotion compensable object exists from among the unit regions segmentedby the reformed grid.

To achieve the objects above, there is provided a compaction methodusing a grid moving method for an object image, including the steps of:a separating step for estimating the motion of the image of an objecthaving shape information and for separating the image of a motioncompensable failed object; a moving step for forming a grid over theimage of the motion compensable failed object separated in theseparating step, segmenting the image into a plurality of unit regions,and moving the grid; a judging step for judging an amount of informationat each position to which the grid is moved in the moving step; adetecting step for detecting a position at which the amount ofinformation is reduced in the judging step; and a compaction step forreforming the grid in accordance with the position detected in thedetecting step and for coding the unit regions in which the image of themotion compensable failed object exists among the unit regions segmentedby the reformed grid.

To achieve the objects above, there is provided a motion estimationmethod using a grid movement of an image of an object, including thesteps of: a separating step for estimating the motion of the image ofthe object having shape information and for separating the image of themotion compensable object; a moving step for forming a grid over theimage of the motion compensable object separated in the separating step,segmenting the image into a plurality of unit regions, and moving thegrid; a judging step for judging an amount of information at theposition to which the grid is moved in the moving step; a detecting stepfor detecting a position at which the amount of information is reducedin the judging step; and a motion estimating step for reforming a gridin accordance with the position detected in the detecting step and forestimating the motion of the image of the motion compensable objectusing the unit regions in which the image of the motion compensableobject exists from among the unit regions segmented by the reformedgrid.

To achieve the objects above, there is provided a grid moving apparatusfor an object image, including: an address generation controller formoving an address start position at which an address is generated by apredetermined distance within a predetermined region of a unit region;an address generator for separating the image of the object into unitregions in accordance with the address start position which the addressgeneration controller outputs and for generating the address; a memoryunit for storing the image of the object having inputted shapeinformation and for outputting the image in accordance with an addressoutputted from the address generator; a region number counter forcounting the number of unit regions in which the shape information ofthe object exists outputted from the memory unit; and minimum unitregion grid selector for selecting an X-axis grid start position XM anda Y-axis grid start position YN at which the minimum number of unitregions is counted from among the number of the unit regions counted bythe region number counter.

To achieve the objects above, there is provided a motion estimationapparatus using a grid moving of an object image, including: a gridmoving unit for adjusting the grid in accordance with an image positionof an object having shape information outputted from an image signalinput unit and for reducing the number of unit regions in which theimage of the object exists; and a motion estimation unit for estimatinga motion of the image of object using the motion of the unit regions ofwhich the number of unit regions is reduced.

To achieve the objects above, there is provided a compaction/motionestimation apparatus using a grid moving of an object image, including:an image separator for separating an image of a motion compensablefailed object and an image of a motion compensable object in accordancewith a motion from an image of an object having shape information; afirst grid moving unit for adjusting the grid in accordance with animage position of the motion compensable failed object separated by theimage separating unit and for reducing the number of unit regions inwhich the image of the motion compensable failed object exists: acompaction unit for coding the image of the object existing in the unitregions of which the number of the unit regions is reduced by the firstgrid moving means; a second grid moving unit for adjusting the grid inaccordance with the image position of the motion compensable objectseparated by the image separating unit and for reducing the number ofunit regions in which the image of the motion compensable object exists;and a motion estimation unit for estimating the motion information ofthe motion compensable object using the unit regions in which the imageof the motion compensable object exists of which the number of the unitregions is reduced.

To achieve the objects above, there is provided a motion estimationapparatus using a grid moving of an object image, including: an imageseparating unit for separating an image of a motion compensable objectin accordance with a motion of an object having shape information; agrid moving unit for adjusting a grid in accordance with an imageposition of the motion compensable object separated by the imageseparating unit and for reducing the number of unit regions in which theimage of the motion compensable object exists; and a motion estimationunit for estimating motion information of the motion compensable objectusing the unit region in which the image of the motion compensableobject exists of which the number of the unit regions is reduced by thegrid moving unit.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus are not limitativeof the present invention, and wherein:

FIGS. 1A and 1B are views showing a conventional grid pattern formed inone image frame, of which:

FIG. 1A is a view showing a conventional grid pattern formed in oneimage frame; and

FIG. 1B is a view showing a conventional unit region which is indicatedas 8×8 pixels;

FIGS. 2A through 2F are views showing various shapes of a conventionalunit region;

FIGS. 3A through 3F are views showing a conventional shape adaptivediscrete cosine transform process;

FIG. 4 a block diagram showing a grid moving apparatus according to thepresent invention;

FIG. 5 is a block diagram showing an address generator of FIG. 4according to the present invention;

FIG. 6 is a view showing an order that an address generator outputs animage of an object stored in a memory of FIG. 4 by separating inaccordance with an X-axis address and a Y-axis address according to thepresent invention;

FIG. 7 is a block diagram showing a region number counter of FIG. 4according to the present invention;

FIG. 8 is a flow chart showing a method for detecting a position atwhich the amount of information is reduced in a grid moving methodaccording to a first embodiment of the present invention;

FIGS. 9A through 9F are views showing a method for extracting an imageof an object in a grid moving method and detecting a position at whichthe amount of information existing in a unit region is a minimum numberaccording to the present invention;

FIG. 10 is a flow chart showing another method for detecting a positionat which the amount of information is reduced in a grid moving methodaccording to a second embodiment of the present invention;

FIG. 11 is a flow chart showing another method for detecting a positionat which the amount of information is reduced in a grid moving methodaccording to a third embodiment of the present invention;

FIGS. 12A and 12B are views showing a method for sequentially outputtingan image of a unit region by moving an X-axis and Y-axis grid startpositions in a zig-zag manner in accordance with a signal flow of FIG.11 according to the third embodiment of the present invention;

FIG. 13 is a view showing another method for detecting a position atwhich the amount of information is reduced in a grid moving methodaccording to a fourth embodiment of the present invention;

FIG. 14 is a view showing another method for detecting a position atwhich the amount of information is reduced in a grid moving methodaccording to a fifth embodiment of the present invention;

FIGS. 15 and 16 show tables showing a comparative result value of theconventional method and of the methods of the various embodimentsaccording to the present invention, of which;

FIG. 15 is a table showing a comparative result value after moving agrid start potion in accordance with an image position of a young woman;and

FIG. 16 is a table showing a comparative result value after moving agrid in accordance with an image position of an old woman;

FIG. 17 is a block diagram showing a motion estimation/compactionapparatus according to the first embodiment of the present invention;

FIGS. 18A through 18C are views showing an image which is reformed bydetecting a position at which the amount of information is reduced froman image of a moving compensable object in a motion estimation methodaccording to the present invention;

FIG. 19 is a block diagram showing another motion estimation/compactionapparatus according to the second embodiment of the present invention;and

FIG. 20 is a view showing an image frame so as to explain a timelapse-based variation according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

A grid moving method for minimizing image information of an object andan apparatus using the grid moving method and a compaction/motionestimation method using the grid moving method and an apparatus thereforwill now be described with reference to FIGS. 4 through 20.

As illustrated in FIG. 4, reference numeral 31 denotes an addressgeneration controller for moving an address start position at which anaddress is generated within the range of the X-axis and Y-axis by apredetermined distance, and reference numeral 33 denotes an addressgenerator for generating X-axis and Y-axis addresses so that the imageof an object can be segmented to a unit region and sequentiallyoutputted in accordance with an address start position which the addressgeneration controller 31 generates, and reference numeral 35 denotes amemory for sequentially storing an image of an object havingpredetermined shape information and segmenting and outputting a unitregion in accordance with an address which the address generator 33generates.

As shown in FIG. 5, in the address generator 33, an X-axis rangedetermination unit 331 determines the range of the X-axis of a unitregion in accordance with the size information of the inputted image,and the Y-axis range determination unit 333 determines the range of theY-axis of a unit region in accordance with the size information of theinputted image.

Here, when the ranges of the X-axis and Y-axis are identical, the sizeof the unit region can be determined using either the range of theX-axis or the range of the Y-axis.

The region address generator 335 of the address generator 33 judges theranges of the X-axis and Y-axis of the unit region which is determinedby the X-axis range determination unit 331 and the Y-axis rangedetermination unit 333, segments the X-axis and Y-axis with respect tothe unit region of the image of the object stored in the memory 35 basedon the address start position outputted from the address generationcontroller 31, and sequentially outputs the X-axis and Y-axis addressesof the segmented unit region.

The memory 35 separates the image stored therein by one unit region fromanother unit region in accordance with X-axis and Y-axis addresses whichare sequentially generated by the region address generator 335. Forexample, as shown in FIG. 6, the image of the object of the unit regionis sequentially outputted, and then the image of the object of the nextunit region is sequentially outputted.

In the drawings, as shown in FIG. 4, reference numeral 37 denotes aregion number counter for counting the number of unit regions in whichthe image of the object among the signals outputted from the memory 35exists.

As shown in FIG. 7, in the region number counter 37, a unit regioncounter 371 counts the clock signal and segments the unit region. Ajudging unit 373 separates the unit region of the outputted object inaccordance with the output signal of the unit region counter 371 andjudges as to whether the image of the object exists. An adder 375 addsthe judgment signal of the judging unit 373 and then outputs the numberof unit regions in which the image of the object exists.

In the drawings, as show in FIG. 4, reference numeral 39 denotes aminimum unit region grid selector for selecting the X-axis and Y-axisgrid positions at which a minimum number of the regions is counted bythe region number counter 37.

The minimum unit region grid selector 39 stores the count value when thecounting of region number counter 37 is completed, and controls theaddress generation controller 31 to move the start positions of theX-axis and Y-axis addresses within the range of the X-axis and Y-axis ofthe unit region by a predetermined distance.

Namely, the minimum unit region grid selector 39 moves the startpositions of the X-axis and Y-axis addresses and controls the addressgeneration controller 31 when the counting of the number of the unitregions is completed, and then moves the start positions of the X-axisand Y-axis addresses. The above routines are repeated.

In addition, when the counting of the number of the unit regions inwhich the image of the object exists by moving the start positions ofthe X-axis and Y-axis addresses within the ranges of the X-axis andY-axis is completed, the minimum unit region grid selector 39 judges thestart positions of the X-axis and Y-axis at which the unit region of theminimum number among the number of the counted unit regions anddetermines and outputs the start positions of the judged X-axis andY-axis addresses as the positions at which the amount of information isreduced.

FIG. 8 shows a flow chart of the method for detecting a position atwhich the amount of information is reduced in accordance with a firstembodiment of the grid moving method.

In a step S11, X-axis and Y-axis grid start positions XM and YN areinitialized so as to detect a position at which the amount ofinformation is reduced in which the number of unit regions in which theimage of the object having predetermined shape information exists.

The initial values of the X-axis and Y-axis grid start positions XM andYN are given as XM=0, and YN=0 which are referred to as the initialposition of the minimum unit region positioned at the leftmost anduppermost portion among the unit regions with respect to the image ofthe extracted object.

FIGS. 9A through 9F illustrate a method for adjusting the grid positionso that the image of one object "a" in one image frame containing theimages of a plurality of objects "a, b, c, and d" each havingpredetermined shape information is extracted and then exist in one imageframe.

As shown in FIG. 9A, the grid is indicated with respect to one imageframe containing the images of the plurality of the objects "a, b, c,and d" as shown in FIG. 9B and then the image of the objects isextracted.

There are two methods for extracting the image of the objects. Onemethod is directed to separating and extracting so that each separateimage of the objects "a, b, c, and d" can exist within one region, andthe other method is directed to extracting the image of the objects "a,b, c, and d" so that more than two images can exist within one region.

As shown in FIG. 9C, the image of one object "a" is extracted, and thenthe image of the extracted object "a" can exists within the minimum unitregion 33 so as to detect a position at which the amount of informationis reduced. In addition, the entire grid with respect to the image ofthe extracted object "a" is called a first extraction grid.

The first extraction grid with respect to the image of the extractedobject "a" is segmented into a plurality of unit regions as shown inFIG. 9C.

When the image of the object "a" is extracted, in a step S12, as shownin FIG. 8, the number of the unit regions in which the image of theobject "a" exists based on the X-axis and Y-axis grid start position "A"which is initialized in the step S11 is counted.

As shown in FIG. 9C, the unit region positioned at the left side anduppermost portion of the first extraction grid refers to the minimumunit region 33.

In addition, on the assumption that a unit region which is segmented bythe grid has an 8×8 number of pixels in the X-axis and Y-axisdirections, there are 64 pixels in one unit region.

In the minimum unit region, the initial positions of XM=0, and YN=0refers to the start position "A" of the first extraction grid. As shownin FIG. 9C, the image of the object "a" exists in 14 unit regions.

When counting of the number of the unit regions in which the image ofthe object "a" exists is completed the number of the unit regions whichis counted in a step S13 is stored.

In a step S14, the grid is reformed by moving the X-axis grid startposition XM along the X-axis in the minimum unit region by apredetermined distance "K", which is same as a length of a pixel alongthe X-axis, and in a step S15, it is judged as to whether the X-axisgrid start position is moved along the X-axis M-times.

Namely, it is judged as to whether the X-axis grid start position XM ismoved along the X-axis by more than the size of the unit region.

In the step S15, when the X-axis grid start position XM is not movedalong the X-axis M-times, the steps S12 through S15 are performed, andthen the X-axis grid start position XM is moved along the X-axis by adistance "K", and the number of the unit regions in which the image ofthe object "a" exists is counted and then stored. The above routines arerepeated.

In the step S15, the entire X-axis grid start position XM is movedM-times, the X-axis grid start position XM in which the unit regionhaving the minimum number in a step S16 is counted is determined as anoptimum X-axis grid start position XoM.

In a step S17, the grid is reformed with the optimum X-axis grid startposition XoM and the Y-axis grid start position "YN=0", and the numberof the unit regions in which the image of the object "a" exists.

The counting of the number of the unit regions is completed in the stepS17, in a step S18, the number of the counted unit regions are stored.

In a step S19, the Y-axis grid start position YN is moved along theY-axis by a predetermined distance "L" which is same as a length of apixel along the Y-axis, and in a step S20, it is judged as to whetherthe Y-axis grid start position YN is moved along the Y-axis N-times.

Namely, it is judged as to whether the Y-axis grid start position YN ismoved along the Y-axis by more than the size of the unit region

As a result of the step S20, when the Y-axis grid start position YN isnot moved along the Y-axis N-times by a predetermined distance "L", thesteps S17 through S20 are performed. The Y-axis grid start position YNis moved based on the optimum X-axis grid start position XoM by apredetermined distance "L", and the number of the unit regions in whichthe image of the object "a" exists is counted and then stored. The aboveroutines are repeated.

In the step S20, when the Y-axis grid start position YN is moved by apredetermined distance "L" N-times, the Y-axis grid start position XM inwhich the unit region having the minimum number is counted is determinedas the optimum Y-axis grid start position YoN, and the optimum X-axisgrid start position XoM and the optimum Y-axis grid start position YoNwhich are determined in the steps S16 and S21 are outputted to definethe position "E" at which the amount of information is reduced, as shownin FIG. 9D. The position "B" is an intersecting position of the optimumX-axis grid start position XoM and the optimum Y-axis grid startposition YoN.

Namely, the first embodiment of the present invention of FIG. 8 isdirected to the X-axis grid start position XM, at which the minimumnumber of the unit regions, in which the image of the object exists, iscounted by moving the entire grid along the X-axis by a predetermineddistance "K" M-times, is counted, as the optimum X-axis grid startposition XoM. The Y-axis grid start position YN at which the unitregions having the minimum number in which the image of the objectexists is counted by moving the entire grid along the Y-axis by apredetermined distance "L" N-times based on the determined optimumX-axis grid start position XoM is determined as the optimum Y-axis gridstart position YoN. The determined X-axis grid start position XoM andthe optimum Y-axis grid start position YoN are outputted to defined theposition at which the amount of information is reduced.

Therefore, the first embodiment of the present invention is directed tomoving the entire grid along the X-axis M-times and moving the entiregrid along the Y-axis N-times. Namely, the X-axis and Y-axis grid startpositions XM and YN are moved M+N times, and then a grid start position"B" defined by the optimum X-axis and Y-axis grid start positions XoMand YoN is detected and outputted.

FIG. 10 shows a method for detecting a position at which the amount ofinformation is reduced in the compaction method according to a secondembodiment of the present invention.

In a step S31, the X-axis and Y-axis grid start positions XM and YN areinitialized as XM=0, and YN=0 so as to detect the optimum X-axis andY-axis grid start positions XoM and YoN in which the number of the unitregions in which the image of the object exists becomes minimum.

In a step S32, the number of the unit regions in which the image of theobject exists is counted based on the X-axis and Y-axis grid startpositions XM=0, and YN=0 which are initialized in the step S31, and in astep S33, the number of the unit regions counted in the preceding stepis stored.

In a step S34, the X-axis grid start position XM is moved along theX-axis by a predetermined distance "K", and in a step S35, the X-axisgrid start position XM is moved along the X-axis more than M-times, andthen it is judged as to whether it is moved more than the size of a unitregion.

As a result, when the X-axis grid start position XM is not moved alongthe X-axis more than M-times in the steps S35, the steps S32 through S35are performed. The X-axis grid start position XM is moved along theX-axis by a predetermined distance "K", and the number of the unitregions in which the image of the object exists is counted and stored.The above routines are repeated.

As a result, when the X-axis grid start position XM is moved along theX-axis more than M-times in the step S35, in a step S36, the Y-axis gridstart position YN is moved along the Y-axis by a predetermined distance"L".

In a step S37, it is judged as to whether the Y-axis grid start positionYN is moved along the Y-axis by a predetermined distance "L" more thanN-times.

As a result, when the Y-axis grid start position YN is not moved alongthe Y-axis more than N-times in the step S37, the steps S32 through S37are performed. The Y-axis grid is moved along the Y-axis by apredetermined distance "L", and then the X-axis grid is moved along theX-axis within the range of the unit region by a predetermined distance"K", and the number of the unit regions in which the image of the objectexists is counted and stored. The above routines are repeated.

As a result, when the Y-axis grid start position YN is moved along theY-axis more than N-times in the step S37, the X-axis grid start positionXM and the Y-axis grid start position YN at which the unit region havingthe minimum number in which the image of the object exists is countedare determined as an optimum X-axis grid start position XoM and anoptimum Y-axis grid start position YoN, and then the determined optimumX-axis and Y-axis grid start positions XoM and YoN are outputted todefined the position at which the amount of information is reduced.

The second embodiment of the present invention of FIG. 10 is directed tomoving the entire grid along the X-axis by a predetermined distance "K"M-times and to moving the entire grid along the Y-axis by apredetermined distance "L" M-times, and further moving the entire gridalong the X-axis by a predetermined distance "K" M-times and to movingthe entire grid along the X-axis by a predetermined distance "L" M-timesso as to count the number of the unit regions in which the image of theobject exists. In addition, the X-axis and Y-axis grid start positionsXM and YN at which the unit region having the minimum number is countedare determined as the optimum X-axis and Y-axis grid positions to definea position at which the amount of information is reduced and then areoutputted.

Therefore, the second embodiment of the present invention of FIG. 10 isdirected to moving the X-axis and Y-axis grid start position XM and YNby a predetermined distance "K" and "L" M×N times and outputting theX-axis and Y-axis grid start positions XM and YN, at which the minimumnumber of unit regions is counted.

The embodiments of the present invention of FIGS. 8 and 10 are directedto moving the grid start position along the X-axis by a predetermineddistance "K", to moving the grid start position "A" along the Y-axis bya predetermined distance "L" and to detecting the optimum X-axis andY-axis grid start positions XoM and YoN.

However, the embodiment of the present invention of FIGS. 8 and 10 arefurther directed to gradually moving to the Y-axis by a predetermineddistance "L" and to the X-axis by a predetermined distance "K" anddetecting the optimum X-axis and Y-axis grid start positions XoM and YoNand outputting the position at which the amount of information isreduced.

With regard to the first and second embodiments of the grid movingmethods, as shown in FIGS. 8 and 10, a way of determining the grid startposition of X-axis first followed by determining the grid start positionof Y-axis is described for illustrative purpose.

As indicated in the brackets of FIGS. 8 and 10, the grid moving methodscan also be processed by determining the grid start position of Y-axisfirst followed by determining the grid start position of X-axis.

FIG. 11 shows a method for detecting a position at which the amount ofinformation is reduced in the grid moving method according to a thirdembodiment of the present invention.

In a step S41, the X-axis and Y-axis grid start positions XM and YN areinitialized to 0 so as to detect the optimum X-axis and Y-axis gridstart positions XoM and YoN at which the number of the unit regions inwhich the image of the object exists becomes minimum.

In a step S42, the number of the unit regions in which the image of theobject exists is counted from the initialized X-axis and Y-axis gridstart positions XM and YN, and in a step S43, the number of the countedunit regions is stored.

In a step S44, the X-axis grid start position XM is moved along theX-axis M-times, and it is judged as to whether the Y-axis grid startposition YN is moved along the Y-axis N-times.

As a result, when the X-axis grid start position XM is not moved alongthe X-axis more than M-times or when the Y-axis grid start position YNis not moved along the Y-axis more than N-times, in a step S45, theX-axis and Y-axis grid start positions XM and YN are moved within theunit region in a zig-zag manner by predetermined distances "K" and "L",and then the steps S42 through S45 are performed.

Thereafter, the number of the unit regions in which the image of theobject exists is counted and stored. The routines of moving the X-axisand Y-axis grid start positions XM and YN are repeated.

Here, there are two methods of moving the X-axis and Y-axis grid startpositions XM and YN in a zig-zag manner by predetermined distances "K"and "L". For example, as shown in FIGS. 12A and 12B, there is shown afirst method for moving to the direction indicated by the arrow and asecond method for moving to the direction indicated by the arrow.

In the step S44, when the X-axis grid start position XM is moved alongthe X-axis M-times, and the Y-axis grid start position YN is moved alongthe Y-axis N-times, in a step S46, the X-axis grid start position XM andthe Y-axis grid start position YN at which the unit regions of theminimum number are counted are determined as the optimum X-axis gridstart position XoM and the optimum Y-axis grid start position YoN, andthen the determined optimum X-axis grid start position XoM and thedetermined optimum Y-axis grid start position YoN are outputted todefine the position "B".

Namely, another embodiment of the present invention of FIG. 11 isdirected to moving the entire grid within the range of the X-axis andY-axis of the unit region in a zig-zag manner and to counting the numberof the unit regions in which the image of the object exists.

Therefore, the third embodiment of the present invention of FIG. 11 isdirected to moving the X-axis and Y-axis grid start positions XM and YNby predetermined distances "K" and "L" M×N times and determining theX-axis and Y-axis grid start positions XM and YN, at which a minimumnumber of unit regions is counted, as the position "B", as shown in FIG.9D, at which the amount of information is reduced.

FIG. 9D shows an example for reforming the grid to the position at whichthe amount of information is reduced which is determined in accordancewith the embodiments of the present invention of FIGS. 8, 10, and 11.

Here, the optimum X-axis grid start position XoM which is referred to asthe position at which the amount of information is reduced existing inthe unit region of the minimum number of the image of the object "a" isfive (M=5), and the optimum Y-axis grid start position YoN is six (N=6).

In addition, as a result that the optimum X-axis and Y-axis grid startpositions XoM and YoN are moved along the image position of the object"a", the number of the unit regions in which the image of the object "a"exists is reduced from 14 to 7.

In the above embodiments, the square-shaped unit region or therectangular-shaped unit region which are defined by the X-axis andY-axis are described.

Various forms of the unit region may be used so as to implement theobjects of the present invention.

For example, as shown in FIGS. 2A through 2F, the 45° rotated square,the hexagonal-shaped form or the like may be used. In addition, morethan two different shapes which are capable of dividing the image frameinto a predetermined shape at a regular interval may be combined so asto form the unit regions.

FIG. 13 shows a flow chart of a method for detecting the position atwhich the amount of information is reduced in a grid moving method inaccordance with a fourth embodiment of the present invention.

In a step S51, the X-axis and Y-axis grid start positions XM and YN areinitialized as 0 so as to detect the position at which the number of theunit regions in which the image of the object exists, becomes minimum.

In a step S52, the number of the unit regions in which the image of theobject exists from the X-axis and Y-axis grid start positions XM=0 andYN=0 which are initialized in the step S51 is counted, and in a stepS53, the number of the unit regions counted in the step S52 isdetermined.

In a step S54, the Y-axis grid start position YN is moved along theY-axis by a predetermined distance "L", and in a step S55, it is judgedas to whether the Y-axis grid start position YN is moved along theY-axis more than N-times.

As a result, when the Y-axis grid start position YN is not moved alongthe Y-axis more than N-times, the steps S52 through S55 are performed.The routines that the Y-axis grid start position YN is moved along theY-axis by a predetermined distance "L", and the number of the unitregions in which the image of the object exists is counted and storedare repeated.

As a result, when the Y-axis grid start position YN is moved along theY-axis by a predetermined distance "L" more than N-times in the stepS55, in step S56, the Y-axis grid start position YN at which a minimumnumber of unit regions exists is determined as the optimum Y-axis gridstart position YoN.

When the optimum Y-axis grid start position YoN at which the minimumnumber of unit regions exists is determined in the step S56, in stepS57, the grid is reformed based on the determined optimum Y-axis gridstart position YoN, and in step S58, the unit region of the currentX-axis row in which the image of the object exists is counted.

Namely, as shown in FIG. 9E, the unit regions in which the image of theobject among the unit regions of the first row of the X(1) row in theX-axis direction exists is counted.

In step S59, the number of the counted unit regions is stored.

In step S60, the grid start position XM of the X(1) row is moved alongthe X-axis by a predetermined distance "K", and in step S61 it is judgedas to whether the X-axis grid start position XM of the X(1) row is movedalong the X-axis by a predetermined distance "K" more than M-times.

As a result, when the X-axis grid start position XM of the X(1) row isnot moved along the X-axis more than M-times in the step S61, the stepsS58 through S61 are performed, and the routines that the X-axis gridstart position XM of the X(1) row is moved along the X-axis by apredetermined distance "K", and the unit region in which the image ofthe object among the unit regions of the X(1) row exists is counted andstored are repeated.

In the step S61, when the grid start position XM and the X(1) row ismoved by a predetermined distance M-times, in a step S62, the grid startposition XM of the X(1) row at which the minimum number of unit regionsamong the currently counted unit regions is counted is determined as theoptimum X(1) row grid start position X1M.

In step S63, it is judged as to whether the row refers to the last rowof the X-axis, and when the row is not referred to as the last row ofthe X-axis, in a step S64, the row is moved along the next row, and thenthe steps S58 through S64 are performed.

The above routines are repeatedly performed, and the row of the X-axisis sequentially moved along X(1), X(2), X(3), X(4), and X(5), and thegrid start position XM of the X(1), X(2), X(3), X(4), and X(5) rows atwhich the minimum number of unit regions in which the image of theobject exists is counted are determined as the grid start positions(X1M, X2M, . . . ) of the optimum X(1), X(2), X(3), X(4), and X(5) rows.

In the step S64, when the row refers to the last row of the X-axis, theoptimum Y-axis grid start position YoN, the optimum grid start positions(X1M, X2M, . . . ) of the X(1), X(2), X(3), X(4), and X(5) are outputtedas positions at which the amount of the information is reduced.

FIG. 14 shows the flow chart of a method for detecting the positions atwhich the amount of information is reduced in the grid moving method inaccordance with a fifth embodiment of the present invention.

In step S71, the X-axis and Y-axis grid start positions XM and YN areinitialized as 0 so as to detect the positions at which the number ofthe unit regions in which the image of the object exists becomesminimum.

In step S72, the unit region in which the image of the object existsamong the unit regions of the current X-axis row is counted.

Namely, the unit region in which the image of the object exists amongthe unit regions of the X(1) row is detected and counted.

When the count of the unit regions is completed in the step S72, in stepS73, the number of counted unit regions is stored.

In step S74, the X-axis grid start position XM of the X(1) row is movedalong the X-axis by a predetermined distance "K", and in step S75, it isjudged as to whether the X-axis grid start position XM of the X(1) rowis moved by a predetermined distance "K" more than M-times.

In the step S75, when the grid start position XM of the X(1) is notmoved by a predetermined distance "K" more than M-times, the steps S72through S75 are performed. The routine that the X-axis grid startposition XM of the X(1) row is moved by a predetermined distance "K",and the number of the unit regions in which the image of the objectexists is counted is repeatedly performed.

In the step S75, when the X-axis grid start position XM of the X(1) rowis moved along the X-axis by a predetermined distance "K" more thanM-times, the grid start position XM of the X(1) row at which the minimumnumber of unit regions among the currently counted unit regions of theX(1) is counted is determined as the optimum X(1) row grid startposition X1M.

In step S77, it is judged as to whether the row refers to the last rowof the A-axis, and when the row is not the last row of the X-axis, instep S78, the row is sequentially moved along the next row of theX-axis, namely, to the X(2), X(3), X(4), and X(5) rows, and the stepsS72 through S78 are performed, and the routines that the grid startposition XM of the X(2), X(3), X(4), and X(5) at which the minimumnumber of unit regions in which the image of the object exists iscounted is determined as the grid start positions (X1M, X2M, . . . ) ofthe optimum X(2), X(3), X(4), and X(5) rows are repeatedly performed.

In the step S77, when the row refers to the last row of the X-axis, instep S79, it is judged as to whether the Y-axis start position YN ismoved along the Y-axis by a predetermined distance "L" more thanN-times.

In the step S79, when the Y-axis grid start position YN is not movedalong the Y-axis by a predetermined distance "L" more than N-times, instep S80, the Y-axis grid start position YN is moved along the Y-axis bya predetermined distance "L", and the steps S72 through S80 arerepeatedly performed.

Namely, the number of the unit regions in which the image of the objectexists is counted by moving the Y-axis grid start position YN along theY-axis by a predetermined distance L" and by sequentially moving thegrid start position XM of the X(1), X(2), X(3), X(4), and X(5) by apredetermined distance "K" from the position to which the Y-axis gridstart position YN is moved. In addition, the grid start position XM ofthe X(1), X(2), X(3), X(4), and X(5) rows at which the minimum number ofunit regions is counted is sequentially determined as the grid startpositions (X1M, X2M, . . . ) of the optimum X(1), X(2), X(3), X(4), andX(5) rows.

In the step S80, when the Y-axis grid start position YN is moved by apredetermined distance "L" more than N-times, in step S81, the numbersof the unit regions which are counted at the grid start positions (X1M,X2M, . . . ) of the optimum X(1), X(2), X(3), X(4), and X(5) rows whichare determined at the position to which the Y-axis grid start positionYN is moved are all summed.

In addition, in step S82, as a result of the sum, the position at whichthe minimum number of unit regions is counted is judged as the Y-axisgrid start position YN, and the judged Y-axis grid start position YN isdetermined as the optimum Y-axis grid start position YoN. The grid startpositions (X1M, X2M, . . . ) of the X(1), X(2), X(3), X(4) and X(5) rowsat which the minimum number of unit regions of the minimum number iscounted is judged as the optimum Y-axis grid start position YoN aredetermined as the grid start positions (X1M, X2M, . . . ) of the optimumX(1), X(2), X(3), X(4) and X(5) rows. In addition, the determinedoptimum Y-axis grid start position YoN and the grid start positions(X1M, X2M, . . . ) of the X(1), X(2), X(3), X(4), and X(5) are outputtedas the position at which the amount of information is reduced.

The result of the reformation of the grid in accordance with theposition at which the amount of information is reduced which is obtainedby the embodiments of FIGS. 13 and 14 are shown in FIG. 9E.

Here, in the fourth and fifth embodiments of FIGS. 13 and 14, an exampleof moving the Y-axis grid start position YN and then the X-axis gridstart position XM so as to detect the optimum grid start position isdescribed.

Namely, the present invention is directed to detecting the position atwhich the amount of information is reduced in which the image of theobject exists in the minimum number of unit regions by changing theX-axis grid start position XM and the Y-axis grid start position YN asshown in FIGS. 13 and 14.

Similarly, the result of the reformation of the grid to the position atwhich the amount of information is reduced by changing the X-axis gridstart position XM and the Y-axis grid start positions in each column(Y1N, Y2N, Y3n, Y4N and Y5N) is shown in FIG. 9F.

With regard to the fourth and fifth embodiments of the grid movingmethods, as shown in FIGS. 13 and 14, a way of determining the gridstart position of each row of X-axis after determining the optimumY-axis grid start position is described for illustrative purpose.

As indicated in the brackets of FIGS. 13 and 14, the grid moving methodscan also be processed by determining the grid start position of eachcolumn after determining the optimum X-axis grid start position.

In addition, in the second and third embodiments of the presentinvention of FIGS. 10 and 11, the square-shaped unit region and therectangular-shaped unit region have been explained. So as to implementthe embodiments of the present invention, the unit region may be formedin various shapes. The unit regions may be moved by separating the rowof the X-axis or the row of the Y-axis. In addition, the unit region maybe formed in a 45° rotated square shape and then the unit region issegmented by a slant grid. The unit region may be also formed of movableslant grid.

For example, when detecting the position at which the amount ofinformation is reduced by moving the unit regions of a row to theX-axis, as shown in FIG. 2A, a unit region may be formed as a triangleusing two slant grids 15 and 17 opposed to the X-axis grid 11. Whendetecting the position at which the amount of information is reduced bymoving the unit region of the row of the Y-axis to the X-axis, as shownin FIG. 2B, a unit region may be formed as a triangle using two slantgrids 15 and 17 opposed to the Y-axis grid 13.

In addition, when detecting the position at which the amount ofinformation is reduced by moving a unit region in an inclination manner,as shown in FIG. 2C, the unit region may be formed as a 45° rotatedsquare using two opposed slant grids 15 and 17.

In the present invention, a method of extracting the image of the object"a" and positioning it into the minimum number of unit regions has beendescribed.

So as to implement the embodiment of the present invention, more thantwo images of the objects "a, b, c, and d" are selectively extracted,and then the position at which the amount of information is reducedexisting in the minimum number of unit regions may be detected.

In addition, the predetermined distances K and L of the X-axis andY-axis grid start positions XM and YN have the reference of the numberof the pixels existing in the range of the unit region.

For example, the X-axis and Y-axis grid start positions XM and YN may bemoved by the length of the unit pixel within the range of the X-axis andY-axis of the unit region.

However, since the information with respect to the chrominance signalfrom the video signal is referred to 1/2 of the information of theluminance signal, the moving distances K and L" of the X-axis and Y-axisgrid start position in XM and YN consideration of the information withrespect to the chrominance signal and the luminance signal arepreferably referred to as the length of two pixels.

In addition, in this embodiment of the present invention, an examplethat the position at which the image of the object exists in the minimumnumber of unit regions has been described as one position; but aplurality positions at which the amount of information is reduced may beconsidered.

Therefore, in the present invention, when a plurality of positions atwhich the amount of information is reduced are considered, the unitregion is divided into sub-regions having the size of (M/2)×(N/2), andthe grid start positions XM and YN are moved by predetermined distances"K and L" within the range of the X-axis and Y-axis of the dividedsub-regions, and the X-axis and Y-axis grid start positions at which theimage of the object exists in the minimum number of unit regions isdetected and outputted as the position at which the amount ofinformation is reduced.

Namely, on assumption that the size of the unit region is formed of16×16 pixels, the sub-region has 8×8 pixels. In addition, the grid startpositions XM and YN are moved by predetermined lengths "K and L" withinthe number of pixels of the sub-region which is divided into 8×8 pixels.

Thereafter, the X-axis and Y-axis grid start positions at which theminimum number of unit regions in which the image of the object existsis detected, and then the X-axis and Y-axis grid start positions areoutputted as the positions at which the amount of information isreduced.

In addition, when a unit region is divided into the sub-regions, aplurality of positions at which the amount of information is reduced forcounting the minimum number of unit regions may be generated.

Therefore, in the present invention, when a unit region is divided intothe sub-regions, and a plurality of the optimum X-axis and Y-axis gridstart positions XoM and YoN are generated, a proper one among themshould be selected.

At this time, as one position to be selected becomes closer to theinitial X-axis and Y-axis grid start positions XM=0 and YN=0, the valueof the motion vector becomes smaller, and the information amount isdecreased. In addition, when estimating the motion, since the estimationerror occurrence rate becomes lower, the X-axis and Y-axis grid startpositions in which the distances is nearest therebetween based on theinitial grid start positions XM=0 and YN=0 are determined as thepositions at which the amount of information is reduced.

The results of FIGS. 15 and 16 were obtained by adjusting the positionsof the X-axis and y-axis grids with respect to the image of the objectand coding using a computer simulation.

The image used for the object was that of a young woman and an oldwoman, and the number of the image frames was 50, respectively.

Here, the compaction with respect to the image of the object in theconventional art refers to a shape adaptive discrete cosine transformmethod. Here, a fixed block grid(FBG) shape adaptive discrete cosinetransform (SADCT) refers to a method of adjusting the position of theX-axis grid and Y-axis grid and coding in accordance with the first,second and third embodiments of FIGS. 8, 10, and 11.

In the fourth embodiment of FIG. 13, a method of adjusting and codingthe position of the X-axis grid and Y-axis grid in accordance with theX-axis grid and Y-axis grid refers to a variable block grid (VBG) shapeadaptive discrete cosine transform (SADCT) 1-X method and a variableblock grid (VBG) shape adaptive discrete cosine transform (SADCT) 1-Vmethod.

In the fifth embodiment of FIG. 14, a method of adjusting and coding theposition of the X-axis grid and Y-axis grid in accordance with theX-axis grid and Y-axis grids refers to a variable block grid (VBG) shapeadaptive discrete cosine transform (SADCT) 2-X method and a variableblock grid (VBG) shape adaptive discrete cosine transform (SADCT) 2-Ymethod. In the fifth embodiment of FIG. 14, a method of separating andextracting the image of the object and then coding in accordance withthe X-axis grid is referred to a variable block grid (VBG) shapeadaptive discrete cosine transform (SADCT) 2-X method (by the object).

In this embodiment, an image of the object between N-1 and N frames ofthe original image is extracted, and the result between the conventionalcompaction method which is directed to performing the shape adaptivediscrete cosine transform(SADCT) without varying the position of theX-axis grid and Y-axis grid from the extracted image and the compactionmethod of the present invention was analyzed.

The comparison method was conducted by judging how much transmission bitrate occurs as the occurrence bits per pixel(BPP) per frame and thenumber of regions per frame when the pixel of the object is identicalwith the peak signal to noise ratio(PSNR) which is the objective picturequality evaluation reference.

FIG. 15 shows the average result which is obtained by an experiment of50 frames with respect to the image of the young woman.

As shown in the table of FIG. 15, in the conventional method ofperforming the SADCT without varying the X-axis grid and Y-axis grid,the average peak signal to noise ratio(PSNR) value was 36.46 db, thenumber of the average occurrence bits was 751, and the number of theaverage BPP was 1.21, and the number of the average unit regions was20.71.

Meanwhile, after reforming the grid using the X-axis and Y-axis which ismoved so that the image of the object can exist in the minimum number ofunit regions, the FBG-SADCT was performed. As a result, the average PSNRwas 36.37 db, and the number of the average occurrence bits was 719, andthe average BPP was 1.16, and the number of the average unit regions was18.65.

In a state that the objective PSNR is similar, the FBG-SADCT of thepresent invention had the average number of the occurrence bits reducedby 32 bits, the BPP was reduced by 0.05, and the number of the averageunit regions was reduced by 2.06.

In addition, when moving the X-axis grid and Y-axis grid afterseparating and dividing the image of the object a better result appearedaccording to the result of the embodiments of the present invention.

As a result of the VBG-SADCT 2-X method with respect to the image of theobject, the average PSNR value was 36.3 db, and the number of theaverage occurrence bits was 694, and the average BPP was 1.12, and thenumber of the average regions was 16.82.

Therefore, in the present invention, it is possible to reduce theaverage occurrence bit rate by 57 bits performing the VBG-SADCT by theimage of the object after adjusting the position of the grid inaccordance with the position in which the image of the object existscompared to the conventional method which is directed to performing theSADCT without moving the position of the grid in accordance with theposition at which the image of the object exists. In addition, in thepresent invention, the average BPP is reduced by 0.09, and the number ofthe average unit regions is reduced by 3.89.

FIG. 16 shows the result which is obtained by performing the SADCTwithout varying the grid in the conventional method with respect to theimage of the object among the image of the old woman and the resultwhich is obtained by performing the FBG-SADCT and the VBG-SADCT aftervarying the position of the grid in the compaction method according tothe present invention.

As a result, it is possible to reduce the amount of bits by about 8-10%by performing the VBG-SADCT 2-X rather than by performing the SADCT bythe image of the object.

Meanwhile, FIG. 17 shows a block diagram showing the compaction/motionestimation apparatus according to a first embodiment of the presentinvention, which is directed to detecting the grid moving position andthe position at which the amount of information is reduced with respectto the image of the object having predetermined shape information andestimating the compaction and motion after reforming the grid inaccordance with the position at which the amount of information isreduced.

In the drawings, reference numeral 41 denotes an image signal input unitfor inputting the image of the object having predetermined shapeinformation. Reference numeral 43 denotes a grid moving unit for movingthe position of the X-axis grid and the Y-axis grid in accordance withthe position in which the image of the object exists and for detecting aposition at which the image of the object exists in the minimum numberof unit regions.

In addition, the grid moving unit 43 having the same construction as thegrid moving apparatus as shown in FIG. 4 is directed to sequentiallystoring the image of the object which is inputted by the image signalunit 41, moving the grid start position with respect to the stored imageof the object at a predetermined distance within the range of the X-axisand Y-axis, and separating the image of the object into a plurality ofunit regions in accordance with the moved grid start position. Inaddition, the grid moving unit 43 is directed to judging and countingthe unit regions in which the image of the object exists among the unitregions and outputting the X-axis and Y-axis grid start positions atwhich the minimum number of unit regions among the counted values iscounted as the positions at which the amount of information is reduced.

In the drawings, reference numeral 45 denotes a compaction unit forreforming the X-axis grid and the Y-axis grid in accordance with thepositions at which the amount of information is reduced outputted fromthe grid moving unit 43 and for coding the image of the object.

The compaction unit 45 is directed to reforming the grid in accordancewith the positions at which the amount of information is reduced,namely, which is referred to as the X-axis grid start position andY-axis grid start position at which the image of the object exists inthe minimum number of unit regions. Here, the positions at which theamount of information is reduced is detected by the grid movingapparatus and the grid moving method.

As a method for coding the image of the object of the unit regions usingthe compaction unit 45, there are many methods.

For example, the compaction is performed using SADCT, DCT, vectorquantumization or the like.

In the drawings, reference numeral 47 denotes a motion estimation unitfor estimating the motion of the image of the object. Here, the motionestimation unit 27 is directed to reforming the grid in accordance withthe positions at which the amount of information is reduced, which isdetected by the grid moving apparatus and the grid moving method,segmenting the unit regions in which the image of the object exists inthe reformed grid, and generating the motion information by estimatingthe varied amount of the segmented unit regions.

On the assumption that the image of the object as shown in FIG. 18A isgiven, when indicating the grid as shown in FIG. 18B so as to estimatethe motion of the image of the given object, the number of the unitregions in which the image of the object exists in each row is referredto 3, 5, 4, 4, 4, 5, 7, 8, 8. Namely, the images of the motioncompensable object exist in all 48 unit regions.

Therefore, the present invention is directed to estimating the motion byreforming the grid from the above-mentioned object as shown in FIG. 18Cin accordance with the positions at which the amount of information isreduced which are detected by the grid moving apparatus and the gridmoving method.

As a result of the reformation of the grid in accordance with thepositions at which the amount of information is reduced, the number ofthe unit regions in which the image of the object exists in each row isreferred to 3, 4, 4, 3, 3, 5, 7, 7, 8. Namely, it appeared that thenumber of the unit regions is reduced to all 44 unit regions. Therefore,it is possible to reduce the motion information amount by estimating themotion of the image of the object with respect to the reduced number ofunit regions.

FIG. 19 shows a compaction/motion estimation apparatus according to asecond embodiment of the present invention which is directed toseparating the image of the object having predetermined shapeinformation into the motion compensable object and the motioncompensable failed object, coding the separated motion compensablefailed object, and estimating the motion of the motion compensableobject.

Here, in the drawings, reference numeral 51 denotes an image signalinput unit for inputting an image signal having predetermined shapeinformation to be coded.

Reference numeral 53 denotes an image separation unit for separating theimage signal outputted from the image signal input unit 51 into theimage of the background image having no motion and the image of themoving object having motion.

Here, the changed region of the image of the moving object is judgedusing the information varied between the previously inputted image andthe currently inputted image.

FIG. 20 shows the time-based variation of the inputted image frame. Asshown therein, it appeared that a plurality of intermediate image framesBi, . . . , Bj exist between the frame Pα of the previously inputtedimage and the frame P of the currently inputted image.

Therefore, for the image of the moving object, there is a forward motionestimation of estimating the frame Bi of the intermediate image from theframe Pα of the previous image and a backward motion estimation methodof estimating the frame Bj of the intermediate image of the frame P ofthe current image.

The image of the moving object estimated by the image separation unit 53is separated into moving information of the motion compensable object,shape information of the motion compensable object, signal informationof the motion compensable failed object, and shape information of themotion compensable failed object.

In the drawings, reference numeral 55 denotes a first grid moving unitfor detecting the positions at which the amount of information isreduced using shape information of the motion compensable failed objectseparated by the image separation unit 53.

The first grid moving unit 55 has the same construction as the gridmoving unit 43 and as the grid moving apparatus of FIG. 4. The firstgrid moving unit 55 is directed to adjusting the grid position inaccordance with the position at which the image of the motioncompensable failed object separated by the image separation unit 53 andoutputting the position in which the image of the motion compensablefailed object exists in the minimum number of unit regions.

In the drawings, reference numeral 57 denotes a compaction unit forcoding a signal of the position at which the amount of information isreduced outputted from the first grid moving unit 55 and the image ofthe motion compensable failed object in accordance with the position atwhich the amount of information is reduced detected the grid movingmethod.

The compaction unit 57 is directed to reforming the grid using theposition at which the amount of information is reduced as a referenceand coding the image of the motion compensable failed object of the unitregion in which the image of the motion compensable failed object existsin the unit region of the reformed grid using the methods of SADCT, DCT,or vector quantumization.

In the drawings, reference numeral 59 denotes a second grid moving unithaving the same construction as the grid moving apparatus of FIG. 1, thegrid moving unit 43, and the first grid moving unit 55. The first gridmoving unit 55 is directed to adjusting the position of the grid inaccordance with the position at which the image of the motioncompensable object separated by the image separation unit 53 andoutputting the position in which the image of the motion compensableobject exists in the minimum number of unit regions.

Reference numeral 61 denotes a motion estimation unit which is directedto reforming the grid in accordance with the signal of the position atwhich the amount of information is reduced outputted from the secondgrid moving unit 59 and the position at which the amount of informationis reduced detected by the grid moving method, segmenting the image ofthe motion compensable object into the unit regions from the reformedgrid and generating the motion information using the variation amount ofthe segmented unit regions.

As described above, the grid moving method for minimizing imageinformation of an object and an apparatus using the grid moving methodand the compaction/motion estimation method using the grid moving methodand an apparatus thereof according to the present invention are directedto forming the minimum number of unit regions having the image of theobject by adjusting the position of the grid in accordance with theimage position of the object, coding the image of the object withrespect to the minimum number of unit regions, and generating the motioninformation, thus achieving a higher compaction rate, whereby the amountof the data to be stored and transmitted can be significantly reduced.

Although the preferred embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas described in the accompanying claims.

What is claimed is:
 1. A grid moving apparatus for minimizing coding andtransmission of image information of an object, comprising:addressgeneration control means for moving an address start position at whichan address is generated by a predetermined distance within apredetermined region of a unit region; address generating means forseparating the image of the object into unit regions in accordance withthe address start position which the address generation control meansoutputs and for generating the address; memory means for storing theimage of the object having inputted shape information and for outputtingthe image in accordance with an address outputted from the addressgeneration means; region number counting means for repeatedly countingthe number of unit regions at each address start position generated bysaid address generation control means in which the shape information ofthe object exists outputted from the memory means; and minimum unitregion grid selecting means for selecting an X-axis grid start positionand Y-axis grid start position at which the minimum number of unitregions is counted from among the number of the unit regions counted bythe region number counting means.
 2. The apparatus of claim 1, whereinsaid address generation means includes:X-axis range determining meansand Y-axis range determining means for determining the X-axis range ofthe unit region and the Y-axis range of the unit region in accordancewith size information of the inputted image of the object; and regionaddress generation means for separating the X-axis range and Y-axisrange of the unit region which are determined by the X-axis rangedetermining means and the Y-axis range determining means from theaddress start position outputted from the address generation controlmeans.
 3. The apparatus of claim 2, wherein said X-axis range and Y-axisrange of the unit region are determined by one size determining meanswhen the X-axis range and the Y-axis range of the unit region areidentical to each other.
 4. The apparatus of claim 1, wherein saidregion number counting means includes:region counting means for countinga clock signal and for separating the unit region; shape informationexisting judging means for separating the unit region of the imageoutputted from the memory means in accordance with an output signal ofthe region counting means; and region number adding means for counting ajudging signal of the shape information existing judging means and foroutputting the number of the unit regions in which the image of theobject exists.